The present invention provides a friction minimized bearing structure, which is operated in a same-speeded and contrary-directional manner, and actives an inner ring and an outer ring to rotate synchronously in contrary directions. Otherwise, rollers are mounted on a supporting gear module, the roller contacts with the outer ring of the bearing structure and rotate in contrary directions within the same rotation speed, therefore achieves a friction-minimized bearing structure. The bearing structure of present invention makes the relative velocity between the balls and the inner ring, and the outer ring is relatively down to zero or nearly zero. With such manner, an inner friction between the balls, inner ring and the outer ring may be relatively down to zero or nearly zero so as to achieve the objective of minimizing the friction.
